The use of windshield wipers to clear a vehicular windshield or other vehicular window or surface has been standard since almost the start of the automotive era. A wiper blade, rotatably affixed, or otherwise positioned, at the vehicular surface, is caused to be moved across the surface. The movement of the wiper blade causes rain, snow, ice, and other precipitation to be removed from the surface. Depending upon the amount of precipitation, the motion of the wiper blade across the surface must be repeated, sometimes at regular intervals.
While very early implementations of windshield wipers required that an operator manually apply the moving forces to cause the movement of the wiper blade across the windshield, or other, surface, pneumatic, and then, electric, actuators were soon used to provide the moving forces. Through use of the pneumatic or electrical motors to provide the moving forces, the operator no longer was required to provide the moving force. Generally, the moving forces provided by the pneumatic actuator or electric motor provide for repeated movement of the wiper blade at a fixed rate.
The rate of precipitation and the speed of movement of the vehicle are determinative of the frequency, or rate, at which the wiper blade is needed repeatedly to be moved across the windshield, or other, surface to remove the precipitation thereon. Most simply, a single-speed, viz., a simple “on-off”, actuator or motor is used. When single-speed operation is provided, the wiper blade is caused to be moved, repetitively, at a single, fixed rate. Or, the actuator or motor provides more than one fixed rate of operation, e.g., a low-speed rate and a high-speed rate of operation. An operator selects which of the two, or more, fixed speeds at which the actuator or motor causes movement of the wiper blade across the windshield, or other vehicular surface. The speed is selected best to remove the precipitation falling against, or forming on, the surface that is to be cleared.
Intermittent windshield wiper operation has, in more recent years, also been provided. When in a so-called intermittent mode of operation, the rate at which the wiper blade is caused to be moved across the vehicular surface is less than at the low-speed, fixed rate. Typically more than just a single, additional, low-speed rate at which the wiper blade is movable across the vehicular surface, intermittent operation permits an operator to select any of a range of repetition rates at which the wiper blade moves across the surface.
Some conventional intermittent wiper systems utilize a rotary dial that contains multiple contacts. User rotation of the dial into a selected dial position is determinative of the selected repetition rate. While the user is able to select the repetition rate through the positioning of the rotatable dial, the user typically is unable to know precisely the selected repetition rate but through a trial-and-error process. That is to say, a user positions the dial in a first position to select an initial repetition rate. And, then the dial is again rotated, to increase or to decrease the repetition rate to obtain a repetition rate that corresponds to the desired repetition rate. Sometimes, multiple iterations of dial rotation are carried out to arrive at the desired repetition rate.
The conventional capability of merely estimating the repetition rate and then modifying the selected repetition rate until the desired repetition rate is obtained distracts the user, typically the driver of the vehicle, from other driving tasks. Any distraction of the driver when operating the vehicle in inclement weather conditions is potentially hazardous. In addition to the rotatable dial, an additional actuator is typically used, increasing the complexity and cost of the wiper assembly user interface.
An economical windshield wiper assembly, permitting intermittent operation and having a user interface permitting easier use to obtain the desired repetition rate of the wiper blade, would therefore be advantageous.
It is in light of this background information related to windshield wiper systems that the significant improvements of the present invention have evolved.